At first I thought, "well, that's just weird". But I think you may be on to something. Since health insurance companies will not be willing to pay for such a procedure it will become a sign of wealth and status since it will only be afforded to those who can pay for it. Eventually those with bellybuttons will have their's removed later in life as they become more affluent. There will then be a backlash as the truly naveless look for a way to differentiate themselves from the nouveau naveless. The rich will begin to purchase bellybuttons on the blackmarket from third-world donors willing to give up their bellybuttons for what amounts to a years wages in their undeveloped country. These blackmarket bellybuttons will then be transplanted onto the bellies of the rich. But one bellybutton won't be enough. They'll have multiple bellybuttons transplanted on their bellies in intricate designs. The more you can afford the higher your status. Eventually those with one bellybutton and those nouveau naveless will also start adding bellybuttons or removing them or reducing to one depending on the fashion of the day. Eventually you won't be able to tell the rich from the middle class or from the poor and the world will be a better place for it. Of course you will be able to tell who the plastic surgeons are. They'll be the one's laughing all the way to the bank.

As long as you're playing games with bellybuttons, why not go all the way. Implant a small TV (flat screen) so that your bed partner has something to watch if sex doesn't work out. Batteries may be a problem.

Somebody's been reading Dr. Suess books. . . "Sneeches" in particular.